Thelymitra venosa R.Br.
Macdonaldia cyanea Lindl. in Bot. Reg. 25, 1840, Swan Riv. App. 1.
Thelymitra? uniflora Hook. f. Fl. Antarct. 1, 1844, 70.
T. cyanea (Lindl.) Benth. Fl. Aust. 6, 1873, 323.
Type locality: Near Port Jackson, N.S.W. Apparently fairly widely distributed in eastern Australia and Tasmania and recorded (Hatch, loc. cit. p. 395) from New Caledonia.
Plant at fl. c. 10–50 cm. tall, often gregarious. Lf linear, fleshy, roundly thickened on margins and keel and so ± trefoil-shaped in T.S. Infl. 1–c. 6-fld. Per. c. 10–15 mm. long, most commonly blue, less commonly white, petals and occ. other tepals strongly striped with darker blue, occ. wholly pink without obvious stripes. Lateral sepals narrow. Petals broad-elliptic. Labellum broadly obovate, sts slightly crenate towards tip or mucronate. Column short; anther bent forward, almost fully exposed, ending in 2 short horns; column-arms ± ribbon-like, tending to twist inwards into ½–1½ turns of a loose spiral, tip sts unevenly notched; post-anther lobe lacking; a narrow band of clear, blister-like, crowded calli lies across back of anther between bases of column-arms and sts extends up their lower margins.
DIST.: N., S., St., Ch., A.
Mostly in poorly drained sites, from sea level to above timber line.
FL. 12–3.
T. cyanea. Original locality: "Van Dieman's Land". T. venosa var. cyanea (Lindl.) Hatch in T.R.S.N.Z. 79, 1952, 391.
T. uniflora. Original locality: "Lord Auckland's Group". Type: K(?).
T. venosa var. cedricsmithii Hatch in T.R.S.N.Z. 79, 1952, 390. Defined as similar to but considerably smaller than var. venosa, "differing mainly in the simple labellum and in the lobes of the column-wing, which are shorter than the anther". The "hypotype" is said to be the "illustration over the name Th. unifolia [sic.] (Cheeseman, Illus. N.Z. Flora 2, 1914, t. 193a)" these figures having been drawn from "specimens collected on the Waimarino Plains, at the western base of Ruapehu, altitude 3,000 ft.". No specimen suitable for a lectotype has been found at AK.
The characters used to differentiate 3 vars within T. venosa are: size of plant; crenulation of labellum; width of per.segs; degree of involution and toothing of column-arms, and their length relative to anther. All these vary greatly within and between populations. Column-arms if very short are naturally less able to twist.
White-fld plants turn up sporadically amongst predominantly blue fls in several districts, and these have been seen to turn blue during pressing. Less common are fls of deep rose pink. In pakihi land south of Westport, in January 1967 when most fls were over, those remaining, numbering together many hundreds, were almost all of uniform very pale salmon pink, the few exceptions being of the usual blue. Both Townson and Morgan note, on specimens at AK, the pink or flesh colour of fls appearing late in summer in this same general area.
In T. venosa the per. is more distinctly zygomorphic than in other N.Z. spp. and fls are inclined to close by folding symmetrically and ± flat about the middle line. The open fls face more sideways and less upwards than in other spp.